Since its inception, stem cell research has remained controversial.

Despite the recent successes in Cincinnati, the captive breeding program has remained controversial.

The question of whether one of the three texts was the standard version from which the other two were originally translated has remained controversial.

Their grievances, while remaining controversial, were incorporated into public discourse.

Throughout his life Subhas remained controversial, but was a downtoearth person.

The policy remained controversial, and was finally repealed in 2011, removing open sexual preference as a reason for dismissal from the armed forces.

The severity of the sentences he passed became and has remained controversial.

For these reasons, debate about the origins of the pogrom has remained controversial.

Although microtubules have been known to influence cell migration for many years, the mechanism by which they do so has remained controversial.

The extent to which there was a sexual element, or a physical sexual relationship, involved in these cases remains controversial.