The returning officer already has the power to ask a person to produce a piece of identity. If the person does not have an ID card, an oath can be taken stating that the person is indeed who he or she says they are, and that he actually lives in the place he claims to live in. That is already allowed.
I want it to be very clear that the returning officer can ask for ID, but he is the only one able to do so at a polling station. A scrutineer does not have this power. Scrutineers are not allowed to speak directly to a voter and ask for a piece of ID. Only the returning officer can do that. Therefore, a scrutineer would have to convince a returning officer to do just that. That is an important clause in the act. It already exists.
Conflicts at the polling station occur when a scrutineer asks the returning officer to check a person's identity and the returning officer believes it is not necessary, or believes that the scrutineer is disputing people's identity too often. At that point, a returning officer can make a judgment call and decide not to require identification, which may insult the scrutineer, who believes that his or her rights have been trampled upon. But those rights belong to the returning officer and not the scrutineer. That is already the case.
Now, if you wish to talk about a piece of identity for each voter, that is an entirely different issue that I can talk about if you like.