The first case of the mishnah in Makkos 2a involves two witnesses testifying that a particular kohen is a ben-gerushah v’chalutzah. The mishnah states that if the witnesses are proven to be eidim zommemin they do not receive the traditional punishment of kaasher zamam (in this case to become challalim); they receive malkos instead. Tosafos (d”h Meidin) ask on the mishnah from the concept known as eidus she’ee atta yachol l’hazimah. The halacha is that for eidus to be accepted it must be “yachol l’hazimah” - it must be possible to both falsify the witnesses through imanu hayissem as well as to punish them with kaasher zamam. Tosafos therefore ask that if it is true that eidim zommemin in the case of ben-gerushah v’chalutza don’t receive the punishment of kaasher zamam, why then is their testimony acceptable at all? Why isn’t it considered eidus she’ee atta yachol l’hazimah?
Tosafos offer two opposing answers to this question. First, Tosafos suggest that the malkos the eidim zommemin receive in the case of ben-gerushah v’chalutzah is in fact halachically considered kaasher zamam. Accordingly, testimony on a ben-gerushah v’chalutzah is yachol l’hazimah and therefore acceptable in court. Tosafos second answer takes the opposite approach. In reality, when it comes to creating a ben-gerushah v’chalutzah, there is no need at all for the eidus to be yachol l’hazimah. This is so because the entire source for the din of yachol l’hazimah is actually the pasuk of kaasher zamam. Since the gemara excludes eidim zommemin of ben-gerushah v’chalutzah from the punishment of kaasher zamam, they are excluded from the din of yachol l’hazimah as well.
It emerges from the second answer of Tosafos that the requirement for eidus sheyachol l’hazimah doesn’t apply to eidus on a ben-gerushah v’chalutzah at all. This position presents us with an interesting question. We know that the requirement of yachol l’hazimah in eidus actually expresses itself in two ways. First, there is the requirement that Tosafos highlight – that the eidim must be able to theoretically receive the punishment of kaasher zamam for their eidus to be accepted. This requirement is mentioned explicitly in several sugyas in shas.
The requirement of yachol l’hazimah, however, expresses itself in a second way as well. The gemara in Sanhedrin (41b) discusses the requirement upon Beis Din of derishah v’chakirah (to investigate and question the eidim) and mentions two kinds of questioning – chakiros and bedikos. The gemara explains that chakiros are fundamentally different than bedikos in that chakiros are questions of where and when the eidus took place; bedikos, on the other hand, are questions of what exactly took place. When it comes to chakiros, the gemara says that the eidim must answer for their eidus to be accepted. Why? Because if the time and place haven’t been specified the eidus will not be yachol l’hazimah in the sense that other eidim won’t be able to say imanu hayissem. When it comes to bedikos, on the other hand, this isn’t true. Although it is a mitzvah upon Beis Din to conduct bedikos, the eidus is still acceptable even if the eidim don’t answer the questions. Since the information being sought from the bedikos isn’t needed for imanu hayissem, that information is not required.
Based on this, we can now ask on the second answer of Tosafos. If it’s true that eidus on a ben-gerushah v’chalutzah doesn’t need to be yachol l’hazimah, does that mean that the eidim don’t need to answer the chakirah’s? Is testimony on a ben-gerushah v’chalutzah acceptable even if the eidim don’t specify time and place?
The opinion of the Noda B’Yehudah is yes –testimony by a ben gerushah v’chalutzah is acceptable even if time and place aren’t specified according to the second answer of Tosafos. He explains that the requirement upon Beis Din to ask chakiros and the requirement upon the eidim to answer them are completely separate. The requirement upon Beis Din to ask is from the pasuk of v’darashtah v’chakartah and applies to all testimonies – even testimony on a ben gerushah v’chalutzah. The requirement upon the eidim to answer, however, comes from the requirement of eidus sheyachol l’hazimah that is learnt from kaasher zamam. Since this requirement is waived by eidus on a ben gerushah v’chalutzah according to the second answer of Tosafos, the requirement to answer the chakiros is also waived. The Noda B’Yehudah goes further and extends this chiddush to other cases where there is no kaasher zamam, as well.
The Beis HaLevitakes issue with the position of the Noda B’Yehudah. Most significantly, he notes how novel this position is, as it is never mentioned anywhere in shas that there are cases where chakiros - on a level of d’orayssa - need not be answered. More fundamentally, the Beis HaLevi offers a different understanding of the chakiros in general. He explains that in reality the din of yachol l’hazimah is not separate from the requirement upon Beis Din to ask derishos v’chakiros contained in v’darashtah v’chakartah. Rather, the gezairas hakasuv of kaasher zamam (i.e. eidus she’yachol l’hazimah) is that the chakiros that Beis Din asks are a part of the etzem ha’eidus itself. Unlike bedikos, chakiros are required not only from Beis Din’s perspective, but from the perspective of the eidim as well.
The Beis Halevi provides logical proof to his position. He argues that if eidus merely needed yachol l’hazimah as a separate din (and not because it was part of the etzem haeidus) that wouldn’t require such specificity regarding the time of the eidus. After all, let the mazimin come in and say imanu hayissem for the past 50 years. Why the need to specify the exact day, and even time of day? The Beis HaLevi therefore explains that in reality Beis Din ask specifics because of v’darashtah v’chakartah. The din of kaasher zamam then tells us that the specifics of where and when (as opposed to the specifics of what) are part of the etzem ha’eidus and therefore both punished by kaasher zamam and absolutely required. According to the Beis HaLevi, it emerges that eidim need to answer chakiros not as a separate requirement, but rather because it’s not considered eidus at all without certain details.
Based on this, the Beis HaLevi explains that even if the requirement for the eidim to receive the kaasher zamam punishment is waived by eidus on ben-gerushah v’chalutzah, the requirement for them to state the when and where of their eidus is certainly not waived. This is so because that second requirement is mandated not by the mere gezairas hakasuv of kaasher zamam, but rather by the fundamental definition of eidus itself. In Chiddushei R’ Chaim HaLevi Eidus 3:4, R’ Chaim seems to accept the position of his father, the Beis HaLevi. He writes that within the din of derishah v’chakirah there is contained two chiddushim. First, there is the requirement that the eidim be questioned. Second, there is a chiddush that the chakiros themselves are a part of the gufah shel eidus.
 See Sanhedrin 41a regarding a naarah meorassah, Sanhedrin 78a regarding a teraifah, and Babba Kamma 75b regarding modeh b’knas.
 See Nodah BiYehudah Mahadurah Kamma 57.
 See the Beis HaLevi inside for various formulations on how kaasher zamam works together with v’darashtah v’chakartah.