I've not heard of the DMV requiring an ignition interlock device on all refusals or any blow over .08. However, the court can impose it. An ignition interlock device will be required on a DUI with a blow over .15.
not intended as legal advice and this answer does not create an attorney/client relationship.
No, DMV will not require an IID for a first refusal or breath reading under .15 (assuming no minor was in the car), but, as others indicated, the court may do so.
Court suspensions and administrative suspensions are separate and distinct. That's why sometimes the IID is not imposed in court but will be by DMV. It's another reason that it is imperative to have an attorney experienced in handling DUI cases.
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